温拌SBS沥青混合料旋转压实特性

采用旋转压实仪(SGC) 成型温拌SBS沥青混合料试件, 根据体积参数的变化规律确定了最佳拌合温度, 根据旋转压实曲线对温拌沥青混合料和热拌沥青混合料的压实特性进行了对比分析。分析结果表明: 与热拌沥青混合料相比, 用旋转压实法确定温拌沥青混合料成型温度降低约20℃, 动稳定度提高30%, 低温抗裂和抗水损害能力相差不大。在压实初期, 热拌沥青混合料SGC压实曲线的斜率为2.53, 密实能量指数为0.246, 温拌沥青混合料SGC压实曲线的斜率为3.14, 密实能量指数为0.156, 表明温拌沥青混合料具有更好的施工和易性; 在压实后期, 热拌沥青混合料SGC压实曲线的斜率为0.019 5, 密实能量指数为1.95和1.65, 温拌沥青混合料SGC压实曲线的斜率为0.015 2, 密实能量指数为2.61和2.00, 表明开放交通后温拌沥青混合料具有更好的抵抗荷载压密的能力。

Gyratory compaction characteristic of SBS warm mixed asphalt mixture

Superpave gyratory compacter (SGC) was used to make the specimens of SBS warm mixed asphalt mixture (WMA), and the volume characteristics of WMA were compared with hot mixed asphalt mixture (HMA) to determine the reasonable mixing temperature. Furthermore, the slopes and densification energy indexes of SGC compaction curves were introduced to reflect the inherent compaction characteristics of asphalt mixtures. Analysis result indicates that the determined compaction temperature of WMA is lower than HMA by 20 ℃, the dynamic stability of WMA improves by 30%, but its crack resistance at low temperature and its water stability change a little. In the initial stage, the slope of densification curve of HMA is 2.53, and the densification energy index is 0.246. The slope of densification curve of WMA is 3.14, and the densification energy index is 0.156. The result indicates that WMA has better construction workability. In the later stage, the slope of densification curve of HMA is 0.019 5, and the densification energy indexes are 1.95 and 1.65. The slope of densification curve of WMA is 0.015 2, and the densification energy indexes are 2.61 and 2.00. The result indicates that WMA has better capacity to resist the densification under traffic load.10 tabs, 5 figs, 12 refs.